INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 3, No 2, 2012

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1 INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 3, No 2, 2012 Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN The Effect of marble powder and silica fume as partial replacement for cement on mortar Faculty of Engineering, Suez Canal University, Ismailia, Egypt h_mohamadien@yahoo.com doi: /ijcser ABSTRACT Marble powder material (MP) is a very fine powder, obtained as a by-product of marble during the sawing and the shaping, and not recycling it due to environmental problems in the world.the possibility of using it and silica fume (S.F) separately as partial replacement of cement on mortar were studied and evaluated based upon the percentage of the partial cement replacement with both marble powder and silica fume separately. Four types of mortar mixture with same workability, cement to sand ratio of 1:3 and water to cementitious materials ratio of 0.4 were prepared marble powder and silica fume used in mixes separately, once as a partial replacement of cement content and another as an addition to the mix proportion. Replacement and addition ratio of both marble powder and silica fume with cement content separately at 0%, 5%, 10%, 15%, 20%, % and 50 % by weight were investigated. The mechanical properties of mortar were measured in terms of compressive strength at 7 and 28 days and it was observed that the strength developments at 7, and 28 days and the highest development rate of compressive strength was observed at 15% replacement ratio for each the marble powder and silica fume separately. Results showed that the compressive strength increased by 31.4%, 48.3% at 7, and 28 days respectively at 15% replacement ratio of silica fume with cement content and in case of replacement marble powder with cement content the compressive strength increased by 22.7%, 27.8% at 7, and 28 days at 15% replacement ratio of marble powder with cement content respectively. Keywords: mortar, marble powder, silica fume, compressive strength. 1. Introduction The marble has been commonly used as a building material since ancient times. Disposal of the marble powder material of the marble industry, consisting of very fine powder, is one of the environmental problems worldwide today. In this work, a marble powder, obtained as a by-product of marble sawing and shaping, was characterized from a physical and chemical point of view for evaluating the possibility of using it in mortar and concrete production [1]. During the cutting process about 25% marble is resulted in dust [2]. Silica fume (SF) is a waste material that is products during the production of silicon and silicon alloys. The fume is collected by filtering the gases escaping from furnace [3]. The addition of silica fume increases the rate of cement hydration at early hours due to release of OH ions and alkalis into pore fluids. This is attributable to the ability of silica fume to provide nucleating sites to hydration products like lime, calcium silicate hydrates (CSH), and ettringite [4]. It has been reported that silica fume accelerates both C3S and C3A hydration during the first few hours [5]. G. Appa Rao [6] concluded that during the early ages, 3 and 7 days, strength of mortars with silica fume, in general, has been significantly high at any w/b ratio. The rate of strength development between 3 and 7 days was the highest. At w/b ratios 0.35, 0.40, and 0.45, the Received on September 2012 Published on November

2 passing % The Effect of marble powder and silica fume as partial replacement for cement on mortar optimum silica fume contents for achieving highest compressive strength range between 17.5% and 22.5%. 2. Research program The experimental work in this study consisted of the use of silica fume once as a partial replacement of cement content and another as an addition to the mix proportion. Also, the experimental work consisted of the use of marble powder once as a partial replacement of cement content and another as an addition to the mix proportion. In the four cases the silica fume and marble powder was used as ration of 0%, 5%, 10%, 15%, 20%, % and 50% of the cement content. The mechanical properties of mortar were measured in terms of compressive strength at 7 and 28 days. 3. Materials properties Sand, Clean and rounded fine aggregate with size 0.15 to 5 mm was used. Natural sand composed of siliceous materials was used as fine aggregate in this study. Testing of sand was carried out according to the Egyptian Code No [7]. Figure (1) shows the grading of the sand. The physical properties of the sand are given in table (1) % passing Sand % ESS Upper Limet % ESS lower Lime 0 pan Sieve Size mm Figure 1: Grading curve of used Cement, Ordinary Portland Cement (OPC) CEM I 42.5 N. produced by EL-Suez cement company. Testing of cement was carried out as the Egyptian Standard Specifications ESS /2009 [8], where the retained on sieve #170 was less than 10%. Table (2) show the physical properties of Ordinary Portland Cement. The used of silica fume is brought from factories of Egyptian Ferro-alloys company located in Aswan, Egypt. Its physical properties and chemical analysis are given in table (3) and (4), respectively, as obtained from manufacturer. To keep the slump constant for all mixes the super-plasticizer was used. It is supplied from chemicals for modern building company. It meets the requirements of Superplasticizer according to ASTM C type A and F [9]. Its technical data are given in table (5) supplied by the manufacturer. Marble powder is brought from factories of Egyptian marble company. Its physical properties and Chemical analysis is given in table (6), and (7). Table 1: The physical properties of the sand Property Results Specifications Limits Compressive Strength of 3 days 21.4 Not less than 18 ** Standard Mortar (Mpa) 28 days 39.7 Not less than 36 ** Fineness in terms of S.S.A** 3120 >2750 ** International Journal of Civil and Structural Engineering 419

3 The Effect of marble powder and silica fume as partial replacement for cement on mortar (cm 2 /gm) Setting Time ( min ) Initial 135 Not less than 45 ** Final 180 Not more than 600 ** ** Egyptian Code No [7]. Table 2: Physical properties of ordinary Portland cement Property Results Limits Specific Weight ** Bulk Density (t/m 3 ) Clay and Fine Dust Content % by Volume 0.85 Not more Than 3 ** **Limits of ECCS [7]. Table 3: Physical properties of the used silica fume Property Test Results Specific surface area ( cm 2 /gm) 17.2*10 3 Bulk density (kg/m 3 ) 355 Specific gravity 2.15 color Light gray Table 4: Chemical analysis of the used silica fume Oxide Content % Limitation % * SiO min C max Al 2 O max Fe 2 O max CaO max MgO max K 2 O max Na 2 O max SO max H 2 O max Cl max PH fresh 6.0 ±1 max Table 5: Super plasticizer Technical Data Property Technical Data Color Dark brown liquid State Liquid solution Specific gravity 1.2 Chloride content Nil Compatibility with cement All kinds of Portland cement International Journal of Civil and Structural Engineering 420

4 The Effect of marble powder and silica fume as partial replacement for cement on mortar 4. Mix proportion Table 6: Physical properties of marble powder Property Test Results Specific surface area ( 11.4*10 3 cm 2 /gm) Bulk density (kg/m 3 ) 986 Specific gravity 2.5 color Light gray Table 7: Chemical properties of marble powder Compound Oxides Contents Silicon Oxide SiO (%) Aluminum Oxide Al 2 O Ferric Oxide Fe 2 O Calcium Oxide Ca O Magnesium Oxide MgO 2.77 Sodium Oxide Na 2 O 0.91 Potassium Oxide K 2 O 0.63 CL 0.04 S O Loss on Ignition (L.O.I) 34.5 The percentage of sand to cementitious materials (OPC+SF or MP) ratio was kept constant at 3:1 by weight in all mixes as shown in table (8). The SF and MP was used either as a replacement or as an addition of 0%, 5%, 10%, 15%, 20%, % and 50 % of cement content by weight. The water to cementitious materials [W/ (OPC + SF or MP)] ratio was kept constant at 0.4 and the super-plasticizer dose was determined to obtain a constant slump flow diameter of 125 to 145mm. 4.1 Mixing procedure Mixing was done in a standard drum-type mixer in two steps, First: fine aggregate, cement, and silica fume or marble powder were mixed in dry state until the mixture become homogenous, then half of gauging water were added to the dry mixture, and mixed for 2 min. Second: the Superplasticizer admixture added to the remaining water (1/2 of the gauging water) and the mortar mixed by mixer for another 2 min. 4.2 Details of specimen Compression test at 7, and 28 days was carried out on x70.711x mm cubes. All the test specimens were dislodged after 24 hours and then stored under water in curing tanks with room temperature (25±2ºC). The test was carried out according to Egyptian Stander Specifications ESS Part 7 [10]. International Journal of Civil and Structural Engineering 421

5 Mix no. The Effect of marble powder and silica fume as partial replacement for cement on mortar Table 8: Mix proportion for mortar symbols Cement Sand SF MP SP Water kg kg kg kg (C+SF or MP)% (C+SF or MP)% N A SF A SF A SF A SF A SF A SF R SF R SF R SF R SF R SF R SF A MP A MP A MP A MP A MP A MP R MP R MP R MP R MP R MP R MP N= control, A= addition, R= replacement, SF= silica fume, MP= marble powder 5. Test results 5.1 Silica fume replacement cases The results of compressive strength at 7, and 28 days were investigated, table (9) and figure (2) shown the average results of the compressive strength test of plain mortar specimens containing SF with percentage ratio 0%, 5%, 10%, 15%, 20%, %, and 50% as a partial replacement by weight of cement respectively at age 7, and 28 days, results were calculated in MP and presented as a percentage of the corresponding reference mix. It can be seen that, plain mortar specimens showed an increase in the compressive strength with time. Where a value of 22.9 MPa was obtained at 7 days and 26.3 MPa at 28 days for the control mix N. Mortar specimens containing silica fume show higher strength value compared to the references plain mortar at the same ages. Furthermore, the rate of strength gain due to the presences of silica fume was higher with the use of 15% replacement and the rate of strength gain was decreased with the increased in the percentage of silica fume. International Journal of Civil and Structural Engineering 422

6 The Effect of marble powder and silica fume as partial replacement for cement on mortar where, at the age of 28 days the compressive strength of mortar specimens containing 5, 10, 15, 20,, and 50% silica fume as a replacement were about 121.6, 139.9, 148.3, 142.2, 133.8, and 82.1% of that of the references plain mortar specimens, respectively. The increase of strength due to the presences of silica fume can be related to its physical and chemical effects. The principal physical effect of silica fume is that it used as filler, which because of its fineness it can fit into spaces between the cement grins and the strength gain up to 7 days is mainly due to this action. The chemical effect of SF is due to its pozzolanic action. This action can be chemically simplified by the following reaction: S + CH secondary C-S-H (Amorphous silicate from S.F) + (Portland from cement hydration) (calcium silicate hydrate) The secondary calcium silicate hydrate is denser than the primary one and has superior chemical resistance due to its lower lime to silica ratio. The effect of this action can be seen more clearly after 28 days, this result in agreement with references [3, 11, and 12]. The used of SF can be enhancement the transition zone between aggregate and cement baste in concrete. This enhanced bonding is associated with the formation of a dense microstructure in the transition zone of the concrete containing SF, this result in agreement with references [13]. Also, it can be noted that the strength value values of specimens containing 20,, and 50% silica fume replacement by cement weight were less than those of 15% silica fume replacement and this may be due to the higher of silica fume replacement of cement with silica fume (over 15%) the amount of cement in this mix decreased, then the liberated Ca(OH) 2 diminished, which reacted with reacted with the silica fume to given CSH. Table 9: Result of the compressive strength specimens % compressive strength Compressive strength MP Mix symbol of the references plain mortar 7 days 28 days 7 days 28 days N R sf R sf R sf R sf R sf R sf Silica fume addition cases Table (10) and figure (3) shown the average results of the compressive strength test plain mortar specimens and specimens containing SF with percentage ratio 0, 5, 10, 15, 20,, and 50% as an addition of the cement weight respectively at age 7, and 28 days. Results of compressive strength were calculated in MP and as a percentage of the corresponding reference mix result. The silica fume specimens showed higher strength values than the reference plain mortar ones at the same ages. The rate of strength gain due to the addition of silica fume was higher at ratio of 5, 10, 15, and 20% this rate was constant as the percentage of silica fume increased. For instance, at the age of 28 days the compressive strength of mortar specimens containing 5, 10, 15, 20,, and 50% silica fume as an addition were about 114, 1.7, 139.9, 140.7, 142.2, and 143.7% of that of the references plain mortar specimens, respectively. The limited gain of strength as the percentage of silica fume increased from 5, 10, 15, 20,, and 50% may be explained that silica fume content become in excess of the amount required to react with the available Ca(OH) 2, which was formed due to the cement hydration process. International Journal of Civil and Structural Engineering 423

7 The Effect of marble powder and silica fume as partial replacement for cement on mortar Table 10: Result of the compressive strength specimens % compressive strength Compressive strength MP Mix symbol of the references plain mortar 7 days 28 days 7 days 28 days N A sf A sf A sf A sf A sf A sf Marble powder replacement cases The compressive strength was studied at 7, and 28 days. Tables (11) and figure (4) shown the average results of the compressive strength test plain mortar specimens and specimens containing MP with percentage ratio 0, 5, 10, 15, 20,, and 50% as a partial replacement of the cement weight (N, R mp_5, R mp_10, R mp_15, R mp_20, R mp_, and R mp_50, respectively) at age 7, and 28 days. Results of compressive strength were calculated in MP and as a percentage of the corresponding reference mix result. The marble powder specimens showed higher strength values than the reference plain mortar ones at the same ages. The rate of strength gain due to the replacement of marble powder was higher at ratio of 5, 10, and 15% this rate was constant as the percentage of marble powder increased. For example, at the age of 28 days the compressive strength of mortar specimens containing 5, 10, 15, 20,, and 50% marble powder as an addition were about 112.5, 119.4, 127.8, 117.8, 113.3, and 72.2% of that of the references plain mortar specimens, respectively. This is development in compressive strength up to 15% MP may be related to the chemical and physical effect of MP. Also, it can be noted that the strength value values of specimens containing 20,, and 50% MP replacement by cement weight were less than those of 15% MP replacement and this may be due to the higher of MP replacement of cement with MP (over 15%) the amount of cement in this mix decreased, then the liberated Ca(OH) 2 diminished, which reacted with reacted with the MP to given CSH. 5.4 Marble powder addition cases Table 11: Result of the compressive strength specimens % compressive strength Compressive strength MP Mix symbol of the references plain mortar 7 days 28 days 7 days 28 days N R MP R MP R MP R MP R MP R MP The compressive strength was studied at 7, and 28 days. Tables (12) and figure (5) shown the average results of the compressive strength test plain mortar specimens and specimens containing MP with percentage ratio 0, 5, 10, 15, 20,, and 50% as an addition of the International Journal of Civil and Structural Engineering 424

8 Compressive Strength MPa The Effect of marble powder and silica fume as partial replacement for cement on mortar cement weight (N, A mp_5, A mp_10, A mp_15, A mp_20, R mp_, and A mp_50, respectively) at age 7, and 28 days. Results of compressive strength were calculated in MP and as a percentage of the corresponding reference mix result. The marble powder specimens showed higher strength values than the reference plain mortar ones at the same ages. The rate of strength gain due to the addition of marble powder was higher at ratio of 5, 10, 15, and 20% this rate was constant as the percentage of marble powder increased. Where at the age of 28 days the compressive strength of mortar specimens containing 5, 10, 15, 20,, and 50% marble powder as an addition were about 114.1, 125.5, 131.5, 131.1, 129.2, and 127.7% of that of the references plain mortar specimens, respectively. This is development in compressive strength may be related to the chemical and physical effect of MP. Moreover, this is development in compressive strength may be due to that the active SiO 2 in MP can react with the Ca (OH) 2 in concrete to form secondary calcium silicate hydrate and make it chemically stable and structurally dense, this results in agreement with M. S. Hameed et. al., [14] Compressive strength of the concrete has increased with increasing percentages of MP additions at all curing ages. The highest compressive strength appears up to 15% of MP specimen, especially at early curing ages, this result in agreement with reference [15]. Finally, when using MP as additive the compressive strength is lower than using SF addition. Table 12: Result of the compressive strength specimens Mix symbol % compressive strength Compressive strength of the references plain MP mortar 7 days 28 days 7 days 28 days N A MP A MP A MP A MP A MP A MP Compressive strength MP 7 days Compressive strength MP 28 days N Rsf-5 Rsf-10 Rsf-15 Rsf-20 Rsf- Rsf-50 Percentage of s ilica fume reolacement from cement weight % Figure 2: Relation shape between compressive strength and percentage of replacement silica fume from cement weight at 7 and 28 days. International Journal of Civil and Structural Engineering 425

9 Compressive Strength MPa Compressive Strength MPa Compressive Strength MPa The Effect of marble powder and silica fume as partial replacement for cement on mortar Compressive strength MP 7 days Compressive strength MP 28 days N Asf-5 Asf-10 Asf-15 Asf-20 Asf- Asf-50 P ercentage of silica fume addition from cement weight % Figure 3: Relation shape between compressive strength and percentage of addition silica fume from cement weight at 7 and 28 days. Compressive strength MP 7 days Compressive strength MP 28 days N RMP-5 RMP-10 RMP-15 RMP-20 RMP- RMP-50 P ercentage ofmarble powder reolacement from cement weight % Figure 4: Relation shape between compressive strength and percentage of replacement marble powder from cement weight at 7 and 28 days. Compressive strength MP 7 days Compressive strength MP 28 days N AMP-5 AMP-10 AMP-15 AMP-20 AMP- AMP-50 P ercentage of marble poder addition from cement weight % Figure 5: Relation shape between compressive strength and percentage of addition marble powder from cement weight at 7 and 28 days. International Journal of Civil and Structural Engineering 426

10 6. Conclusions The Effect of marble powder and silica fume as partial replacement for cement on mortar Due to analysis of the tests results, the following conclusions can be drawn 1. The maximum value for compressive strength was obtained with the use of 15% silica fume as a partial replacement and the percentage of the increasing 48.3%. 2. The compressive strength of mortar is decreased when Silica fumes contents used as a partial replacement with percentage higher than 15% 3. The compressive strength of mortar increased when Silica fumes contents used as an addition with percentage 5%, 10%, 15% and is almost comparable at percentage higher than 15 % 4. Using marble powder up to 15% as an additive materials enhancement the compressive strength up to 31.5%. 5. Marble powder can be used as alternative materials for silica fume in mortar. References 1. V. Corinaldesi, G. Moriconi, T. R. Naik, (2010) Characterization of marble powder for its use in mortar and concrete United States, Construction and Building Materials, Vol. 24, pp H. Binici, H. Kaplan, S. Yilmaz (2007) "Influence of marble and limestone dusts as additives on some mechanical properties of concrete" Turkey, Scientific Research and Essay, Vol. 2 (9), pp S. E. Z. Falaha (2009) Short and long-term properties of silica fume height strength mortar M. Sc faculty of engineering, materials engineering dept. Zagazig University. 4. J.A. Larbi, A.L.A. Fraay, J.M.J.M. Bijen, (1990) The chemistry of the pore-fluid of silica fume-blended cement systems Netherlands, Cement and Concrete Research, Vol. 20, pp Huang Cheng-yi and R.F. Feldman, (1985) Hydration Reactions in Portland Cement, Silica Fume Blends Canada, Cement & Concrete Research, Vol. 15, No, (4) pp G. A. Rao, (2001) Development of strength with age of mortars containing silica fume India, Cement and Concrete Research, Vol. 31 (2001), pp Egyptian Code No Egyptian Standard Specification /2009 Cement physical and mechanical test. 9. ASTM C type A and F Standard specification for chemical admixtures for concrete. 10. ESS Part 7 "Method of normal curing of test specimens" 11. B. Persson (1998) "Seven-Year Study on the Effect of Silica Fume in Concrete" Sweden, Elsevier Science Ltd., Vol 7, pp International Journal of Civil and Structural Engineering 427

11 The Effect of marble powder and silica fume as partial replacement for cement on mortar 12. R. J. Detwiler and P. K. Mehta, (1989) Chemical and Physical Effects of Silica Fume on the Mechanical Behavior of Concrete Canada, Materials Journal, Vol. 86, PP A. Godman, A. Bentur (1989) "Bond Effects in High-Strength Silica Fume Concretes" Materials Journal, Vol. 86, pp M. S. Hameed and A. S. S. Sekar, (2009) properties of green concrete containing quarry rock dust and marble sludge powder as fine aggregate India, ARPN Journal of Engineering and Applied Sciences, Vol. 4, NO. 4, pp B. Demirel, (2010) The effect of the using waste marble dust as fine sand on the mechanical properties of the concrete Turkey, International Journal of the Physical Sciences, Vol. 5(9), pp International Journal of Civil and Structural Engineering 428